You apparently haven't spent much time in rural Texas.
It also isn't as uncommon as you seem to think it is. Just do a basic Google search with : "explosions go off". Just because you haven't heard an expression doesn't mean it isn't used by others. Food for thought.
Most likely a Freudian slip, intending to say "explosions". Dubya wasn't exactly known for superior oratory skills as president.
e - people apparently don't know what a Freudian slip is
Explosions take place or happen.
Explosives "go off."
I've never heard the expression "explosions go off".
You apparently haven't spent much time in rural Texas.
It also isn't as uncommon as you seem to think it is. Just do a basic Google search with : "explosions go off". Just because you haven't heard an expression doesn't mean it isn't used by others. Food for thought.